Thermal Compound
Posted: Sat Feb 05, 2005 2:41 pm
Gaps are the enemy
Imperfections on the surface of both the CPU die and the Heatsink create an imperfect contact point between the two surfaces. The CPU die and Heatsink might look pretty smooth but when their surfaces meet, the sometimes invisible imperfections on each surface leave gaps in their contact. Air in the gaps acts as a really inefficient heat conductor. These gaps are what thermal paste is meant to fill, so that instead of having poor heat conducting air in those gaps, you have much better conducting thermal paste. Now many of these gaps are microscopic, so much so that you would never notice that the enefficiencies were there at all. But your CPU temperatures will show it: no one in their right mind would run a CPU without a heatsink and thermal interface simply because the raw contact of the two surfaces will NOT transfer enough heat to maintain what enthusiasts would consider to be comfortable temperatures. So now you know why properly applying thermal paste means applying thin layers of paste.
I'd say my money was well spent. That paragraph is straight from your link.
Imperfections on the surface of both the CPU die and the Heatsink create an imperfect contact point between the two surfaces. The CPU die and Heatsink might look pretty smooth but when their surfaces meet, the sometimes invisible imperfections on each surface leave gaps in their contact. Air in the gaps acts as a really inefficient heat conductor. These gaps are what thermal paste is meant to fill, so that instead of having poor heat conducting air in those gaps, you have much better conducting thermal paste. Now many of these gaps are microscopic, so much so that you would never notice that the enefficiencies were there at all. But your CPU temperatures will show it: no one in their right mind would run a CPU without a heatsink and thermal interface simply because the raw contact of the two surfaces will NOT transfer enough heat to maintain what enthusiasts would consider to be comfortable temperatures. So now you know why properly applying thermal paste means applying thin layers of paste.
I'd say my money was well spent. That paragraph is straight from your link.